3091891 has 4 divisors (see below), whose sum is σ = 3372984. Its totient is φ = 2810800.

The previous prime is 3091883. The next prime is 3091897. The reversal of 3091891 is 1981903.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 3091891 - 2³ = 3091883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3091897) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 140530 + ... + 140551.

It is an arithmetic number, because the mean of its divisors is an integer number (843246).

Almost surely, 2^3091891 is an apocalyptic number.

3091891 is a deficient number, since it is larger than the sum of its proper divisors (281093).

3091891 is a wasteful number, since it uses less digits than its factorization.

3091891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281092.

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 3091891 is about 1758.3773770155. The cubic root of 3091891 is about 145.6827256763.

The spelling of 3091891 in words is "three million, ninety-one thousand, eight hundred ninety-one".